Using the Biopac System for

EMG and Hand-Grip Force Measurements

Setting up the Biopac System | Collecting Data | Analyzing the Data

Return to: Tutorial Home Page | ENS 314 Exercise Physiology Lab Web Site

These instructions are not complete as they assume the user can follow on-screen instructions. As this program has many available options that are not presented here, you are encouraged to experiment with the different options and analyses possible.

Setting up the Biopac System to Measure EMG and Hand-Grip Force

MP30 Unit

Hand Dynamometer

Electrode Lead

1. Double-click on the Biopac icon on either the toolbar at the top or the icon on the desktop.
2. Plug a electrode lead cable and hand dynamometer into the MP30 box. Attach the red and black leads to the electrodes on the muscle and attach the white lead to the ground electrode.
3. From the MP30 pulldown menu, select Setup Channels. The channels that the electrode lead cable and dynamometer are plugged into should be indicated by the three checkmarks to the right of the channel numbers.
4. Click on Presets next to the channel used by the electrode leads and select EMG (30-500 Hz).
5. Click on Presets next to the channel used by the hand dynamometer and select Hand Dynamometer (Kg). Close the menu box (clicking on the X in upper right corner).
6. From the MP30 pulldown menu, select Setup Acquisition.
7. Click on the pulldown menu for Acquisition Length and choose a length of time long enough to complete the data collection (e.g. 200 sec).

Collecting Data

1. When everyone and everything is ready, click on the Start button in the lower right corner. To stop data acquisition, click on the Stop button located in the same spot. Should the test need to be restarted, stop the data acquisition and restart by clicking on the Start button. However, whenever restarting data collection, you will be prompted to respond as to whether you want to overwrite the existing data; select Yes.

Analyzing the Data

1. On the Measurement bar located just above the tracings, you will see four or five measurement options showing options such as Time, delta T. You will need these two options, but click on the one of the other Measurement boxes to pull-down the Measurement box menu and select area. This option will measure the area (in mV-sec) above and below the baseline of the EMG spikes.
2. Click on the "I" bar located in the lower right corner.
3. Move the cursor to the beginning of the EMG activity that you want to begin to analyze. Notice that the Time measurement box indicates the time of data selected. Press/hold the left-hand mouse button and drag to the end of the EMG activity that you want to analyze. As you drag, watch the delta T which indicates the length of time that you are highlighting. Record the EMG area. Be sure that the delta Ts are all equal when comparing EMG areas.
4. To collapse the data so that it will fit on a single screen, under Display pulldown menu, select Autoscale Horizontal.